Definitely add a bit of inside shot and rebounding. I would consider adding some passing, jump shot and other guard skills before he caps out. My allstar center capped at tremendous inside def and reb and sensational inside shot. I really wish I had brought up his outside def before he capped. I would think about trying to get average/respectable passing/jump shot/outside d. However, if you want him to make the u21 team, he would need to get his big man skills as high as he can. I'm worried he would cap before you get him high enough. Should still help your team. Good luck.
- TicTacShack